Well, I haven't been able to decide if I need to change anything about Silverbells so I decided to see what other people would change about her. Also, just in case you can't tell her mane is up in pigtails.
I really only have one rule, pretty much go wild as long as you don't take off her bells or change their colour. They are the way they are because I want them that way. But pretty much as long as you don't change the bells you can do whatever you want to with her.